package com.foreknow.demo15;

/**
 * 字符串工具类常用方法
 */
public class UtilDemo {
    public static void main(String[] args) {
        String str = "ads";
        System.out.println(str.length());


        String  x = "2121";
        String y="ren";
        String u =x.concat(y);
        System.out.println(u);
    }
}
